/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Robert Paul Corbett.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*	This product includes software developed by the University of
*	California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#ifndef lint
static char sccsid[] = "@(#)warshall.c	5.4 (Berkeley) 5/24/93";
#endif /* not lint */

#include "defs.h"

void Warshall::transitive_closure(unsigned *R, int n)
{
  register int rowsize;
  register unsigned i;
  register unsigned *rowj;
  register unsigned *rp;
  register unsigned *rend;
  register unsigned *ccol;
  register unsigned *relend;
  register unsigned *cword;
  register unsigned *rowi;

  rowsize = WORDSIZE(n);
  relend = R + n * rowsize;

  cword = R;
  i = 0;
  rowi = R;
  while (rowi < relend)
  {
    ccol = cword;
    rowj = R;

    while (rowj < relend)
    {
      if (*ccol & (1 << i))
      {
        rp = rowi;
        rend = rowj + rowsize;
        while (rowj < rend)
          *rowj++ |= *rp++;
      }
      else
      {
        rowj += rowsize;
      }

      ccol += rowsize;
    }

    if (++i >= BITS_PER_WORD)
    {
      i = 0;
      cword++;
    }

    rowi += rowsize;
  }
}

void Warshall::reflexive_transitive_closure(unsigned *R, int n)
{
  register int rowsize;
  register unsigned i;
  register unsigned *rp;
  register unsigned *relend;

  transitive_closure(R, n);

  rowsize = WORDSIZE(n);
  relend = R + n*rowsize;

  i = 0;
  rp = R;
  while (rp < relend)
  {
    *rp |= (1 << i);
    if (++i >= BITS_PER_WORD)
    {
      i = 0;
      rp++;
    }

    rp += rowsize;
  }
}
